Bashar Al-Assad
Bashar Al-AssadReuters

The White House on Tuesday warned Syrian President Bashar Al-Assad that if he chooses to use chemical weapons, the US and its allies "will respond swiftly and appropriately".

The statement comes ahead of an expected Syrian government offensive against the opposition stronghold in Idlib.

“The United States is closely monitoring the situation in Idlib province, Syria, where millions of innocent civilians are under threat of an imminent Assad regime attack, backed by Russia and Iran,” said a statement from the White House press secretary.

The statement noted that President Donald Trump “has warned that such an attack would be a reckless escalation of an already tragic conflict and would risk the lives of hundreds of thousands of people.”

“Let us be clear, it remains our firm stance that if President Bashar Al-Assad chooses to again use chemical weapons, the United States and its Allies will respond swiftly and appropriately. The United States will continue to work tirelessly with its Allies to find a lasting diplomatic solution to resolve the hostilities in Syria under the auspices of United Nations Security Council Resolution 2254,” the statement concluded.

Syrian government forces are planning a phased offensive in Idlib and surrounding areas held by insurgents fighting Assad, who has been backed by both Russian and Iranian forces in the country’s civil war.

Last week, Iran vowed to continue its military cooperation with the Assad regime, signing a deal with the Syrian government as the two powers gear up for the large-scale campaign in Idlib, which is located in northwestern Syria.

On Monday, Trump himself issued a warning to Assad regarding an attack in Idlib.

“President Bashar al-Assad of Syria must not recklessly attack Idlib Province. The Russians and Iranians would be making a grave humanitarian mistake to take part in this potential human tragedy. Hundreds of thousands of people could be killed. Don’t let that happen!” he tweeted.

The US has twice struck Syrian military installations in response to alleged poison gas attacks. The Syrian government denies using chemical weapons and accuses “terrorists” of being behind chemical attacks.